@DanH: We went there in February (non-holiday), it wasn't busy at all. Compared to, say, Blue Mountain, it was positively EMPTY. Big mountain, multiple lifts and areas, lots of open space to run. Sunshine area was slightly "busy" (that's where the beginners all go), but other than that, tons of space. The trees were practically empty as well, depending where you go.
If you do go to Steamboat, drop @Finndog a line, he's a local that knows all the stashes for any ability level.